Portable freight elevator



July 17, s STOKES PORTABLE FREIGHT ELEVATOR Filed July 26, 1946 3 Sheets-Sheet l July 17, 1951 5, STOKES 2,561,242

PORTABLE FREIGHT ELEVATOR Filed July 26, 1946 3 Sheets-Sheet 2 FIG --5 Sammie] stokgs snverzbor 3 Sheets-Sheet 5 Filed July 26, 1946 r. o b n a v n a K 0 T 5. 6 Z G u m a 6 A CLLt/orrzer Patented July 17, 1951 UNITED STATES PATENT OFFICE PORTABLE FREIGHT ELEVATOR Samuel G. Stokes, Sarnia, Ontario, Canada, as-

signor to Standard Oil Development Company, a corporation of Delaware Application July 26, 1946, Serial No. 686,516

5 Claims.

This invention relates to freight elevators, and more particularly to portable freight elevators.

It is a particular object of this invention to combine in a freight elevator effective and efficient operation with simplicity and economy of construction.

It is another particular object of the invention to furnish a device by the use of which, for the handling and stacking of heavy freight such as barrels and packages containing petroleum products, steel sheets, billets and ingots, savings in time and manpower, coupled with added safety, accrue over the use of prior art freight handling equipment.

It is another particular object of the invention to furnish a device through the use of which the damaging of freight can be almost eliminated and, as a result, essentially simple handling of hazardous type freight such as petroleum products and chemicals can be effected.

In order that the invention may be understood, the accompanying drawings of a particular embodiment are presented. In these drawings, similar numerals refer to similar parts. Figure 1 is a transverse section along the line II of Figure 2. Figure 2 presents a vertical crosssection taken along the line II-II of Figure 1. Figure 3 is an elevation of the structure showing the general arrangement of the device with the platform in lowered and raised positions, respectively and indication of a barrel on the platform in the raised position. Figure 3 also shows the device adapted to facilitate loading of freight from one loading surface to another of unequal height. Figure 4 presents an enlarged sectional elevation on the line IVIV of Figure 2.

The device is shown in Figure 2 as consisting of a cylinder I sealed at its lower end by means of a head l2 in threaded engagement with the cylinder. Securely attached to the head and adjacent to the lower end is a pressure inlet l3 with an inlet pipe M. A piston l5 which reciprocates in the cylinder is shown as being constructed of a tubular member closed at its lower end by means of piston head l6 adapted to have a close fit with the bore of the cylinder Ill. On the lower surface of the piston head, a packing cup I1 is provided. This packing cup I1 may be made of rubber, leather or similar material, and is attached to the piston head l6 by means of the screw l8 with washer l9. The platform 20 is rotatably mounted so as to'permit free movement in any direction at right angles to the cylinder. In Figures 2 and 4 particularly, a tubular memher '22 is shown as being rotatably mounted in the cylinder, thus permitting free movement in any direction at right angles to the cylinder of the platform to which it is attached. The platform 20 is attached to the tubular member 22 by welding or other such means, and with the underside of the platform abutting against the top end 23 of the plunger l5. Added bearing surface at this point is obtained by means of the spacer 24 in threaded engagement with plunger IS. The spacer is provided with an annular flange 25 at its lower end forming a stop member to absorb the impact of the plunger at the end of the return stroke.

The plunger I5 is shown particularly in Figure 4 as being fitted with an annular sleeve 26 in sliding relation with the bore II and the outside cylinder wall of the plunger l5. Securely attached to the top end of the sleeve 26 is the flange 21. The flange 21 is also bolted to a flan e 28 of corresponding dimensions. Thus, when operating when the plunger is at the end of its upward stroke, the upper portion 29 (Figure 2) of the piston head I6 is abutting against the lower portion 30 of the sleeve 26, just above the vent hole 50 for allowing air to be drawn in on the downward movement of the piston and discharge of air on the upward stroke. The structure thus set forth constitutes a lift assembly, forming one unit of the device.

As shown in detail by Figs. 1 and 2, the lift assembly, including the cylinder l0, platform 20 and their respective related parts, is mounted in a support structure consisting of a two-section collar 3| encircling and rigidly clamping the cylinder II by means of the bolts 32. Extending vertically and securely attached to each half of the collar 3| are connecting links 33 with bearing members 34 extending outwardly from the upper portion of the connecting links and attached thereto by means of welding or other such means. The two portions of the structure consisting of the collar 3|, connecting links 33 and bearing members 34 are joined by means of bolts 32 and 35. Clearly, this structure may be fabricated from a plate in two single units. The outer ends of the members 34 are provided with trunnion type bearings 36, each formed of two substantially semi-circular portions welded, or otherwise joined, to the outer surfaces of the members 34 adjacent their ends. Each semicircular portion is provided with a flange part at its inner end which, in the assembled unit, forms a collar portion 31. When thus assembled as a unit, engaging the lift assembly in the manner described, the support structure provides a lift assembly support.

A rectangular-shaped bridge frame member for bridging the gap which may exist between two loading surfaces, as between a Warehouse platform and. the floor of a freight car or truck bed, is provided to receive the lift assembly support structure. The bridge frame,- as shown: in Figs. 1, 2 and 3, is formed of a pair of spaced,.angleiron, side rail members 38 disposed with their vertical legs inwardly and in substantially parallel relation, the ends of the members 38 being connected by transverse, side rail end connecting elements 39, formed of strap iron, and attached to the lower surface of the horizontal leg'portions, adjacent each end thereof. The members 38 are spaced one from another at substantially the distance between the exterior face of the collars 3?. Midway of the length of the members 38, semi-circular recesses M! are formed in the vertical legs of the members 38, intermediate the end connecting elementstil to receive the trunnion ends of the lift assembly support, with the collars 3'1 disposed inwardly of thevertical leg portions of members 38. v

In order to maintain the lift assemb1y,-its .support, and bearing member in fixed relation to the rectangular bridge frame member during operation of the device, a lockingplate Aidepends from and is fiush with the outer edgeoi each angle iron 38. Ihe-plates ll arecentered with the recesses ii] and trunnions 3E5, andare provided with centered bolt holes "42 v in their lower portions. g i

Cooperating with the locking plates ll to provide for a fixed, but adjustable angular relationship'betweenthe lift assembly and its support, and the bridge frame member, quadrant plate members 44 are secured to the outer ends'of one-half portion of the trunnions-tii, depending therefrom into parallel, closely spaced, sur face relationship to the locking plates ll. -Arcu ate slotted portions 43 arev provided to-receive locking bolts 45 passedthrough thelockingplate bolt holes 42. The cooperating. plates may 'thus be held in fixed surface engagement by nutson the bolts 45. If desired, the locking bolts 15 may be replaced by equivalent stud beltsaifixed to the plates 4 I. v

As shown by dotted lines -.in.Fig. -3; where the loading floor surfaces are at different-levels the bridgeframe member may be tilted-torest upon the edge portionsof both floor surfaces 'while, by adjustment ofthe lockingbolts t5, the lift assembly may be rotated with itssupport .on trunnions 35 to maintain theplatform ZiI-ina horizontal position. Rotation of theparts-wi-th relation to the vertical and horizontalplanes is normally limited to about 30,.-but onlyby-the dimensions of the quadrant. plates 1 and the length of slotted portions 43. p

The inlet pipe Id is connected in apressure tight relationship to the inlet fitting iii-and may be provided with an easily detachablecoupl-ing for connection to valved -air,-steam orhy draul-ic hose or pipe lines.

In operation, one end of the bridge framemem ber is rested on a supporting.surface, -such asa loading platform, whilethe other .endof the member is rested. upon the surface of an adjacent vehicle, such as the floor of-a freight ..car or the bed of a-motor truck, with the.side- -raili elements of the frame extendingibetween'itwo surfaces and with the lift assembly-depending from the frame andlift support-in aspace between the vehicle and the platform. Where required, the relationship of the locking plates 4! and quadrant plate member 44 may be adjusted through the bolts 45 so that regardless of any normal variation in height relationship between the platform and the adjacent vehicle surface, the lift assembly is supported vertically between them, the platform 20 being retained in a substantially horizontal position.

When, as intended, a package such as a barrel, bale or other load is to be transferred from the loading platform to the vehicle or vice versa, and particularly where the transfer is to be made from one level on one surface, to another level on the other surface, the load is moved onto the platform 20 from its initial location, and

the lifts assembly operated either to raise or lower the platform 20 to the desired unloading level of the other surface, and the package then transferred from the platform 26 at that level.

The device of this invention, as indicated by the specific embodiment described -above, is'. an effective and efiicient portable frei'ght elevator for the handling and stacking of such heavy freight materials as barrelsand packages containing petroleum products, heavy rolls of .newsprint and bales of-wood pulp, The device er the invention with. modifications over the design of the specific embodiment has a widefielclof application and is particularly suited for the elevation of freight in transit from loading platforms in warehouses steams hip piers an'dter minalsto railroad freight cars, road transport vehicles and the like. 7

Having described the general design of a device according to the invention with specific illustra tions to a particular embodiment, what is claimed is gaging vsaidside rail elementsintermed-iate said; side rail end connecting elements for limited.

rotation on its axis of support, a lift assembly rigidly secured in said support, aniajor portion dependent therefrom below said bridge frame member, and limit means carried'byaeach ofsai-d support and the frame -member side -.-rail ele-v ments said limit means cooperativelyrelatedto limit rotation of the supporter-1d li-ftassembly with respect to the frame memberyand rigidly tofix their relativeangular relationship as "re quired. I

V 1 Apparatus according to claim l, in which the limit means are slotted iquadrant -3plates secured to the outer'end portions of said lift Support and dependent therefrom; locking-plate elements dependent from -said bridge frame members into parallel surface relation tosaid quadrant plates, and a locking bolt "carried-by each. locking plate engaging each :quad-rant, plate through-its slotted-portion to limit and fixv the angular relationship of said'plates as required.v 3.- In a portable lift includinga bridge'fra-me member having paired side railand side rail end connecting elements in said: member and Ta lift assembly supported for limited-rotation -with reference to said bridge framemember on its axis of support, a lift support comprising a collar rigidly engaging the upper end"of-said= liftassembly, 'opposed'supportarms extending-radially from said collar, -a trunnion bearing .member at the outer end of each arm adapted for giournaled bearing of said collanand arms transverselvrof 1..A.portable lift com-prisinga bridge frame said frame members, and limit means carried by said lift support to limit rotation of its trunnion members with respect to said bridge frame member and rigidly to fix said support in relation to said frame member as required.

4. Apparatus according to claim 3 in which the collar, support arms and trunnion members are joined sectional members, clamping the upper end of the lift assembly by means of said collar.

5. In a portable lift, including a bridge frame member, and a lift assembly support mounted for limited rotation thereon, a lift assembly comprising a casing, in fixed relation to said support and dependent therefrom, closed at its lower end and open at its upper end through an annular flange secured thereto, a hollow piston concentrically disposed in radially spaced relation within said casing, a sleeve member in the radial space between the piston, and casing at the upper end thereof, secured to and dependent from a flange exteriorly engaging said casing flange and secured thereto, an annular piston stop member secured to the piston at its upper REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 796,541 Tompkins Aug. 8, 1905 958,364 Champeon May 17, 1910 1,709,506 Wallace et al. Apr. 16, 1929 1,990,047 McCollum Feb. 5, 1935 2,250,627 Feeney July 29, 1941 

